xref: /freebsd/sys/fs/nfsserver/nfs_fha_new.h (revision ebacd8013fe5f7fdf9f6a5b286f6680dd2891036)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2008 Isilon Inc http://www.isilon.com/
5  * Copyright (c) 2013 Spectra Logic Corporation
6  *
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 /* $FreeBSD$ */
30 
31 #ifndef	_NFS_FHA_NEW_H
32 #define	_NFS_FHA_NEW_H 1
33 
34 #ifdef	_KERNEL
35 
36 #define	FHANEW_SERVER_NAME	"nfsd"
37 
38 /* Sysctl defaults. */
39 #define FHA_DEF_ENABLE			1
40 #define FHA_DEF_READ			1
41 #define FHA_DEF_WRITE			1
42 #define FHA_DEF_BIN_SHIFT		22 /* 4MB */
43 #define FHA_DEF_MAX_NFSDS_PER_FH	8
44 #define FHA_DEF_MAX_REQS_PER_NFSD	0  /* Unlimited */
45 
46 #define FHA_HASH_SIZE	251
47 
48 struct fha_ctls {
49 	int	 enable;
50 	int	 read;
51 	int	 write;
52 	uint32_t bin_shift;
53 	uint32_t max_nfsds_per_fh;
54 	uint32_t max_reqs_per_nfsd;
55 };
56 
57 /*
58  * These are the entries in the filehandle hash.  They talk about a specific
59  * file, requests against which are being handled by one or more nfsds.  We
60  * keep a chain of nfsds against the file. We only have more than one if reads
61  * are ongoing, and then only if the reads affect disparate regions of the
62  * file.
63  *
64  * In general, we want to assign a new request to an existing nfsd if it is
65  * going to contend with work happening already on that nfsd, or if the
66  * operation is a read and the nfsd is already handling a proximate read.  We
67  * do this to avoid jumping around in the read stream unnecessarily, and to
68  * avoid contention between threads over single files.
69  */
70 struct fha_hash_entry {
71 	struct mtx *mtx;
72 	LIST_ENTRY(fha_hash_entry) link;
73 	u_int64_t fh;
74 	u_int32_t num_rw;
75 	u_int32_t num_exclusive;
76 	u_int8_t num_threads;
77 	struct svcthread_list threads;
78 };
79 
80 LIST_HEAD(fha_hash_entry_list, fha_hash_entry);
81 
82 struct fha_hash_slot {
83 	struct fha_hash_entry_list list;
84 	struct mtx mtx;
85 };
86 
87 /* A structure used for passing around data internally. */
88 struct fha_info {
89 	u_int64_t fh;
90 	off_t offset;
91 	int locktype;
92 	int read;
93 	int write;
94 };
95 
96 struct fha_params {
97 	struct fha_hash_slot fha_hash[FHA_HASH_SIZE];
98 	char server_name[32];
99 };
100 
101 SVCTHREAD *fhanew_assign(SVCTHREAD *this_thread, struct svc_req *req);
102 void fhanew_nd_complete(SVCTHREAD *, struct svc_req *);
103 #endif /* _KERNEL */
104 
105 #endif /* _NFS_FHA_NEW_H */
106